[O] Orgmode links trouble with Emacs 24.4 on Windows 7: "ShellExecute failed: ..."

[AW]

hi,

I installed Emacs 24.4 on Windows 7. 

Everything works, except some of my links in orgmode. They worked under Emacs 
24.3, and they work with Emacs 24.4 under Linux.

The non-working links have a certain structure: I'm using shorcuts. I have a 
file "AW-org-file.el", containing lines like:

(setq org-link-abbrev-alist
'(name . "//SBS2011/path/to/folder/%s"))

This file "AW-org-file.el" is required in my .emacs

The links in the org-files look like this:

[[name:filename]]

or

[[name:./path/down/the/folder/filename.pdf]]

With cursor on the link I do "C-c C-o" and get:

"ShellExecute failed: Das System kann die angegebene Datei nicht finden."

(my translation: the system can not find the file).

I'd be thankful for a helping hand,

Alexander